Field of the Invention
The invention is particularly but not exclusively concerned with digital implementation of some of the stages of a radio receiver, and an aim is to achieve a highly linear, high resolution output.
It is desirable to have the analogue-to-digital converter as near the front end of the receiver as possible to obtain the benefits of subsequent digital processing but as a practical matter often the earliest this can be done is at a suitable intermediate frequency (i.f.) stage. For example, this could be a frequency of 2.5 MHz with a bandwidth of 100 kHz.